Vet Insights: Feline Upper Respiratory Infection: Can Cats Pass It to Humans?

While enjoying a cuddle session with your cat, you notice they’re sneezing and have a runny nose. This could be a sign of a feline upper respiratory infection. But the bigger question is: can cats pass these infections to humans?

This article explores everything you need to know about feline upper respiratory infections, from risk factors and causes to signs, vet care and simple ways to keep your cat comfortable.

What is a Feline Upper Respiratory Infection?

A feline upper respiratory infection (URI) is a common illness that affects a cat’s nose, throat, and sinuses. It is often referred to as a “cat cold.” It usually causes sneezing, nasal discharge, and congestion, though some cases can be more severe.

Feline URIs are usually caused by viruses or bacteria, making them highly contagious among cats. Also referred to as feline infectious respiratory disease or feline upper respiratory disease complex (URD), this illness spreads quickly in multi-cat environments.

Shelters, catteries, and multi-cat households are especially vulnerable to outbreaks. While most cases improve with supportive care, more severe infections may require veterinary treatment.

Can Humans Catch Upper Respiratory Infections from Cats?

Now that we've covered the basics, let's address a common question: Are upper respiratory infections in cats contagious to humans? Here’s what you need to know.

Most feline upper respiratory infections are caused by species-specific viruses and bacteria that do not pose a risk to humans. However, in rare cases, Bordetella bronchiseptica can cause illness in immunocompromised individuals, and Chlamydophila felis has been linked to instances of isolated conjunctivitis in humans.

Although zoonotic transmission is very rare, maintaining good hygiene, such as washing hands after handling an infected cat, can further reduce any risk. Anyone who develops respiratory symptoms while their cat is ill should consult a physician as a precaution.

Overall, the risk of contracting a cat’s upper respiratory infection is extremely low, but practicing proper care helps maintain a healthy environment for both pets and people.

What are the Signs and Symptoms of Upper Respiratory Infection in Cats?

Feline upper respiratory infections can cause various symptoms, ranging from mild to severe. Early recognition is key to ensuring proper care and preventing complications. 

If your cat exhibits any of the following signs, monitor their condition closely and consult your veterinarian:

• Runny eyes (eye discharge, clear to colored)
• Fever
• Coughing
• Congestion
• Loss of or decreased appetite
• Swollen mucous membranes around the eyes (conjunctivitis)
• Difficulty breathing (in severe cases)
• Nasal and oral ulcers
• Runny nose (nasal discharge, clear to colored)
• Enlarged lymph nodes
• Blepharospasm (frequent squinting)
• Gagging or drooling
• Sneezing
• Hoarse voice
• Depression or lethargy
• Squinting or eye rubbing

What are the Causes of Feline Respiratory Infections?

The three leading causes of feline upper respiratory infections are viruses, bacteria, and fungi. In this section, we’ll examine each and explain how it contributes to the illness.

Viruses such as FVR and FCV are the primary causes of feline upper respiratory infections.

Feline upper respiratory infections are most often caused by viruses, with feline herpesvirus (FVR) and feline calicivirus (FCV) accounting for 80 to 90% of cases.

FVR, which is related to human chickenpox and cold sores, remains in a cat’s system for life and can reactivate under stress. FCV is highly contagious, often causing oral ulcers and respiratory symptoms, and in some cases, it is linked to "limping syndrome" in kittens. 

Unlike herpesvirus, FCV can survive longer in the environment and requires bleach-based disinfectants for proper elimination.

Bacteria can also play a role in feline upper respiratory infections.

The remaining cases are usually caused by bacteria, such as Chlamydophila felis, which is known for causing conjunctivitis (eye discharge), and Bordetella bronchiseptica, which is often linked to stress and overcrowded environments.

Although rare, Bordetella can infect individuals with weakened immune systems. Other bacteria, such as Mycoplasma, Pasteurella, and Streptococcus, often act as secondary infections, making respiratory symptoms more severe.

Fungal infections can also increase a cat’s risk of developing URIs.

Though less common, fungal infections can also contribute to feline upper respiratory infections. Cats may contract fungi like Cryptococcus or Aspergillus from environments with bird droppings and decaying plants, especially in some geographic regions.

A quick note to remember

These infections spread through direct contact (grooming, touching), aerosol droplets (sneezing, coughing), and contaminated surfaces like food bowls, litter boxes, toys, and human hands. Practicing good hygiene and minimizing stress can help reduce a cat’s risk of infection.

Which Cats are Most at Risk for Upper Respiratory Infections?

Some cats are more prone to upper respiratory infections due to certain risk factors, such as:

Crowded environments accelerate the spread of feline upper respiratory infections.

Crowded environments, such as shelters, breeding facilities, and multi-cat households, increase exposure to contagious viruses and bacteria. Kittens and senior cats, with their weaker immune systems, are especially vulnerable, making them more likely to develop infections like the "kitten cold."

A lack of vaccinations can make your cat more susceptible to URIs.

A cat’s vaccination status plays an essential role in preventing illness. While vaccines may not fully prevent infection, they can help reduce the severity of symptoms. 

Cats that are unvaccinated or behind on their shots face a greater risk of developing severe upper respiratory infections. Likewise, cats with feline leukemia virus (FeLV) or feline immunodeficiency virus (FIV) have compromised immune systems, making them more susceptible to respiratory illnesses.

High stress levels can make your cat more vulnerable to upper respiratory infections.

Stress and illness in cats often go hand in hand. It can weaken the immune system, making infections more likely and triggering flare-ups in herpesvirus carriers. 

Changes such as moving, introducing new pets, boarding, or surgery can all contribute to stress-related illness. Keeping your cat’s environment stable and low-stress can help support their overall health.

Breed, genetics, and activity level can also contribute to a cat's risk of developing URIs.

Certain breeds, especially brachycephalic (flat-faced) cats like Persians and Himalayans, are more prone to upper respiratory infections due to their facial structure, which can make breathing and drainage more difficult. Similarly, outdoor cats are at a higher risk because of increased exposure to infected animals and pathogens.

By recognizing these risk factors, cat owners can take proactive steps to minimize exposure, reduce stress, and keep vaccinations up to date, helping to lower the risk of URIs.

How Do Veterinarians Diagnose Upper Respiratory Infections in Cats?

When a cat exhibits signs of an upper respiratory infection, veterinarians typically diagnose the condition based on clinical symptoms and medical history. Sharing details about when symptoms began, how they have progressed, and the nature of nasal or eye discharge can provide valuable insights for an accurate diagnosis.

In some cases, additional diagnostic tests may be required to determine the exact cause of the infection. Blood tests can help identify underlying health issues and assess dehydration or electrolyte imbalances. PCR testing using eye or mouth swabs is often performed to detect specific viruses or bacteria, such as Chlamydia felis.

For severe or recurring infections, a veterinarian may conduct conjunctival scrapings to test for Chlamydia or Mycoplasma, helping to identify the underlying cause. If a URI is prolonged or severe, veterinarians may recommend imaging tests for a more in-depth assessment. 

X-rays can help detect fungal infections, pneumonia, or chronic respiratory issues, while a nasal endoscopy or CT scan may be used to check for nasal polyps or masses. If lung involvement is suspected, a transtracheal wash can help identify the underlying cause.

A definitive diagnosis is usually made by identifying the infectious agent through testing nasal, throat, or eye secretions.

By understanding the diagnostic process for cat URIs, pet owners can work with their veterinarian to ensure an accurate diagnosis and appropriate treatment.

Supportive Care at Home: What Helps and What to Ask Your Vet

Most URIs need a vet visit first. Alongside your vet’s plan, simple supportive care can keep your cat comfortable while they recover.

Supportive care should complement, not replace, the treatment plan recommended by your veterinarian. Ask your vet before giving your cat any supplement.

With that in mind, here is what to know about supplements and products you may read about:

• L-lysine is an amino acid supplement often discussed for cats with herpesvirus. Research on L-lysine’s effectiveness is mixed, and some studies suggest it may be ineffective or even worsen signs, so ask your vet before using it.

Once your vet has examined your cat, Zumalka’s BREATHE-EZ (CLEAR) is a homeopathic formula designed to help support respiratory health in cats and dogs, promoting comfort and overall well-being. It is not a treatment for upper respiratory infections.

Simple Comfort Care Tips While Your Cat Recovers

• Regularly cleaning your cat’s eyes and nose helps remove discharge and keep them comfortable. Use a soft, damp cloth or vet-approved wipes to gently clear away buildup and prevent irritation.
• Your vet may suggest N-acetylcysteine to help loosen thick secretions (clearer breathing for your cat). Use it only if your vet prescribes it and at the dose they give.
• Keeping your cat well-hydrated helps maintain healthy mucous membranes, and dry nasal passages can worsen congestion.
• Encourage your cat to eat, as upper respiratory infections can reduce their sense of smell and appetite. Offering strong-smelling foods like fish or tasty canned options can help stimulate their interest in eating.
• Stress can trigger flare-ups in cats with feline herpes virus, worsening upper respiratory symptoms. Creating a calm, stable environment helps reduce stress and keeps your cat comfortable.
• Increasing humidity can help alleviate your cat’s breathing difficulties during an upper respiratory infection. Consider using steam therapy by placing your cat in a steamy bathroom (without direct water exposure) for 10 to 15 minutes several times a day to help with nasal congestion.

How Do Veterinarians Treat Upper Respiratory Infections in Cats?

Veterinary guidance is essential for treating a cat's cold, as the best approach depends on the cause and severity. Providing supportive care, especially for viral infections, can help your cat recover comfortably at home.

Antibiotics are often prescribed for secondary bacterial infections, while antiviral medications like famciclovir may be recommended for severe viral cases with herpesvirus. 

Nasal decongestants and anti-inflammatory drugs (NSAIDs), commonly known as "cat cold medicine," can help relieve congestion and discomfort, while antifungal treatments target infections like Cryptococcus. 

Important Note: Never administer NSAIDs to your pet without consulting a veterinarian, as some can be toxic and potentially fatal to animals.

In some cases, polyprenyl immunostimulants may be recommended for feline herpes virus. Isolating infected cats can help prevent the illness from spreading to other pets. For severe cases, hospitalization may be necessary to provide IV fluids, oxygen therapy, and assisted feeding.

Follow your veterinarian’s recommendations carefully and ensure your cat finishes the full course of prescribed medication to support a smooth and complete recovery.

Can You Lower Your Cat’s Risk of Upper Respiratory Infections?

You can’t rule out every URI, but you can lower the risk. Following these guidelines can help protect your feline companion from upper respiratory infections:

Keep your cat indoors to reduce exposure to potential sources of infection.

Keeping your cat indoors helps reduce exposure to infected animals and harmful pathogens, lowering the risk of upper respiratory infections. If you have multiple cats, properly isolating infected pets can prevent the illness from spreading. 

Reduce your pet’s stress levels.

Minimizing stress is essential for your cat’s health. Provide hiding spots, reduce noise, ensure ample space and resources, and ask your vet about calming supplements or try pheromone diffusers to create a calm environment.

Keep your cat’s vaccinations up to date to help prevent infections.

Keeping your cat’s vaccinations current, as advised by your veterinarian, is crucial for preventing upper respiratory infections. Core vaccines safeguard against feline viral rhinotracheitis (FVR) and feline calicivirus (FCV), helping to minimize the severity and duration of illness.

Non-core vaccines, including those for Chlamydophila felis and Bordetella, may be recommended based on your cat’s risk level, particularly in multi-cat or high-density environments.

Both intranasal and injectable vaccines are available for FVR and FCV, with nasal options offering fast, localized protection. Kittens need a series of vaccinations, while adult cats require boosters every 1 to 3 years to sustain immunity.

Keep up with routine vet checkups.

Routine veterinary exams and preventive care help detect health issues early for timely intervention. A pet homeopathy consultation can also help with a general wellness routine. Regular check-ups, vaccinations, and parasite control contribute to your cat’s overall health and longevity.

Good nutrition supports overall health.

A balanced, high-quality diet supports your cat’s overall well-being, and avoiding harmful foods is equally important.

Maintaining proper hygiene is essential when caring for multiple cats.

Good hygiene is key to preventing infections in multi-cat households. Wash your hands thoroughly and change clothes when necessary to reduce the risk of spreading illness between cats. Taking immediate action at the first sign of illness is essential for your cat’s health.

What is Chronic Upper Respiratory Tract Disease in Cats?

Contrary to common belief, feline upper respiratory infection and feline upper respiratory tract disease are distinct conditions, though both are often associated with chronic sneezing and recurrent infections.

Chronic upper respiratory tract disease in cats is characterized by persistent or recurring symptoms such as sneezing, nasal congestion, and eye discharge. A runny or congested nose with thick, yellow, or blood-tinged discharge is common, often resulting in a diminished sense of smell, decreased appetite, and weight loss.

Throat inflammation can also lead to discomfort and drooling. This condition is often associated with persistent viral infections like herpesvirus or calicivirus, particularly when secondary bacterial infections occur.

Other potential causes include fungal infections, nasal polyps, dental disease, trauma, and, in rare cases, cancer.

Diagnosing the condition involves a physical exam, medical history review, and diagnostic tests such as blood work, swabs, X-rays, or biopsies. Your vet may manage signs with antibiotics, antiviral medications and other prescribed treatments.

The primary goal of treatment is to reduce discomfort and enhance your cat’s quality of life. However, chronic cases may continue to recur despite ongoing treatment.

FAQs

How do vets treat an upper respiratory infection in cats?

Treatment depends on the cause. Your vet may prescribe antibiotics or antivirals and will advise on hydration, nutrition, and a calm environment. Always follow your veterinarian’s recommendations.

How long does an upper respiratory infection last in a cat?

An upper respiratory infection in cats typically lasts 7 to 21 days, depending on severity and treatment. Mild cases resolve quickly, while severe or chronic infections may persist. See your vet if signs last more than a few days or get worse.

What helps a cat recover from an upper respiratory infection?

Prompt veterinary care, any antibiotics or antivirals your vet prescribes, hydration, nutrition, and a stress-free environment.

How to help a cat in respiratory distress at home?

To help a cat in respiratory distress at home, increase humidity, keep them calm, and ensure proper hydration. Seek immediate veterinary care, as severe breathing issues require prompt medical attention for the best outcome.

Can a cat survive an upper respiratory infection?

Yes, most cats recover from upper respiratory infections with proper care. Supportive care, hydration, nutrition, and veterinary guidance help. Severe cases may require medical intervention for a full recovery.

Will a cat's upper respiratory infection go away on its own?

Some mild cat upper respiratory infections may resolve on their own, but veterinary care ensures a faster recovery. Supportive care like hydration and nutrition helps. Severe cases require medical attention.

What does a cat's respiratory infection sound like?

A cat with a respiratory infection may have congestion, sneezing, coughing, or wheezing. You might hear raspy breathing, nasal congestion, or mucus-filled sounds. Severe cases can cause labored breathing and require immediate veterinary attention.

Conclusion

Feline upper respiratory infections are common, with symptoms ranging from mild sneezing to severe congestion and nasal discharge. Since viruses and bacteria are the primary causes, veterinary care is crucial for proper diagnosis and treatment.

Vaccinations and stress management are essential for lowering the risk of upper respiratory infections in cats. If your cat develops symptoms, consult your veterinarian promptly for proper care.

About the author

Dr. Simran Mudaliar, BVSc